Remove the thin metal cap in the middle of the hub/drum,loosen the large nut inside it,slacken wheel nuts(bolts in this case),jack up & place axle stands under car, now remove the large hub nut completely,(don't forget to release handbrake) but leave the wheel on because you can pull on it to get the hub off easier, pulling the hub/drum off is sometimes awkward because there may be a wear ridge on the drum.
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